Photographic printing frame



Jan. 10, 1950 J. T. CAMPBELL 2,494,282

PHoToGRAPmc PRINTING FRAME Filed June 19, 1947 HTTOR/YEY stop adjusting screw 21 with rubber bumper 50 is adapted to cooperatively bear against the bottom edge of frame I5, and threadably extends through the outer end of back stop 25 for relative adjustment therein. Lock nut 28 on screw 21 functions to secure said screw in adjusted position.

As viewed in Figure 4 blanket frame I5 cooperatively bears against the adjusting screw 21 which regulates the vertical position of said frame. Being adjustable, it is seen that any other desired position may be attained.

Stop 25 may be moved aside by swinging the same inwardly upon its hinge support 2S whereby the frames may be moved reciprocally at angles for underprinting.

A back stop catch is provided consisting of the flexible strip 41 secured to stop 25' by screw 48. Catch 41 projects upon and extends from the inner end of back stop 25 and cooperatively bears against the outside surface of side wall I I.

Strip 41 has a. rivet 49 adjacent its outer end which is adapted to cooperatively project within a corresponding opening formed in side wall II for receiving said rivet, and tending to retain the back stop in its operative position.

Toggle anchor clips 29 are secured at 30 to the lower forward portions of side walls II. Coil springs 3l are connected at their lower ends to clips 29, while their upper ends are joined at 32 to the lower toggle links 33.

Center toggle links 34 are pivotally mounted centrally by suitable shoulder screws 35 which project into the opposite side portions of blanket frame I5.

Links 34 are pivotally joined at their lower ends at points 3G to the upper ends of links 33. The upper ends of links 34 are joined at 31 to the outer ends of upper toggle links 38. I'he inner ends of links 38 are joined at 3S to the side wall i portions of glass frame I9. The upper toggle links are joined to the glass frame, the center toggle links are pivotally mounted upon the blanket frame, while the lower toggle links are joined to the coil springs 3|.

With blanket frame I retained horizontally by latch 22, glass frame I9 may be lifted by handle 2l. With the spring and fulcrum bracket arrangement the glass frame may be raised with very slight eiort to any position for loading and will remain in that position until moved. No balance weights are required. Under some conditions oi the toggle links and springs said glass frame may open automatically Once it is released.

With the blanket frame loaded the glass fra-mc is pivotally returned to a horizontal position to cooperatively engage the beading upon said blanket frame for sealing engagement therewith. The vacuum communication is now established between the upper surface of the blanket frame and the vacuum reservoir I3.

Then latch 22 is withdrawn through actuation of handle 25 to release blanket frame I5 therefrom. Both frames may now be raised to a vertical position or making prints.

The spring iulcrum arrangement also equalizes the Weight of the loaded frames making it exceptionally easy to swing the same into vertical position for printing. In fact with latch 22 released the two frames under certain conditions will pivotally tip upward automatically un der action of springs 3l Electric motor 40 and vacuum pump 4I coupled together are mounted upon platform 42 secured upon vacuum reservoir or tank I3, which acts as ISO a convenient platform as well as a reinforcement for the side walls I I of the printer.

Vacuum pipe 43 interconnects vacuum pump 4I and reservoir I3, Figure 2, while flexible conduit 44 interconnects reservoir I3 and the upper surface oi' blanket frame I5 for establishing vacuum communication between the glass and blanket frames. Though forming no part of the present invention a three-way valve 45 is provided upon panel 46 for establishing vacuum communication into blanket frame I5, consequently pipe 44 is intermediately joined by said three-Way valve 45.

By this arrangement, after the blanket is loaded with the negative and the sensitized plate, and after the glass frame is again pivoted to a horizontal position in sealing engagement with blanket frame I5, then the control valve 45 is turned on and vacuum is established between the two frames. Once sealed to each other said frames will stay sealed together until the vacuum is released by turning valve to the position;l

With said frames E5 and I9 sealed together it will be seen that the saine will be elevated together to printing position as soon as latch 22, 25 is re-` leased.

I-Iaving described my invention reference should now be had to the claims which follow for determining the scope thereof.

I claim: 1

1. In a vacuum printing frame, a housing, a normally horizontal blanket frame pivotally mounted thereon, a glass frame pivotally mounted upon said bracket frame, a center toggle link pivotally joined intermediate its ends to said blanket frame, an upper toggle link joined at one end to said glass frame and at its other end to the upper end of said center toggle link, a lower toggle link joined at one end to the other end of said center link, and resilient tension means anchored to said housing and joined to the other end of said lower link.

2. In a vacuum printing frame, a housing, a. normally horizontal blanket frame pivotally mounted thereon, a glass frame pivotally mounted upon said blanket frame, a center toggle link pivotally joined intermediate its ends to said blanket frame, an upper toggle link pivotally joined at one end to said glass frame and at its other end to the upper end of said center link, resilient tension means anchored to said housing, and a lower toggle link joined at one end to said resilient means and pivotally joined at its other end to the other end of said center link.

3. In a vacuum printing frame, a housing, a normally horizontal blanket frame pivotally mounted thereon, a glass frame pivotally mounted upon said blanket frame, a center toggle link pivotally joined intermediate its ends to said blanket frame, an upper toggle link pivotally joined at one end to said glass frame and at its other end to the upper end of said center link, resilient tension means anchored to Said housing, and a lower toggle link joined at one end to said resilient means and at its other end pivotally joined to the other end of said center link, whereby with the blanket frame retained against movement said glass frame may be raised with slight eiort to any position, for loading and will remain in that position until moved.

4. In a vacuum printing frame, a housing, a normally horizontal blanket frame pivotally mounted thereon, a glass frame pivotally mounted upon said blanket frame, a center toggle link pivotally joined intermediate its ends to REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PA'I'ENTS Number Number Name Date Klitchi Jan. 6, 1925 Watres May 1, 1934 Sussin Aug. 22, 1939 Mazzoco Aug. 6, 1940 Ulsheimer Sept. 30, 1941 Campbell Jan. 20, 1942 Gaebel Jan. 9, 1945 FOREIGN PATENTS Country Date Great Britain Mar. 13, 1930 

